Hi Mick and all,
It is certainly unusual to see Rockwarblers in granite but not unheard of.
My only personal experience of Rockwarblers in granite is at Evans Crown
Nature Reserve, near Tarana NSW, where I used to see them regularly during
the 1980's. Evans Crown is a granite tor with a good selection of cavities
and caves in the gaps underneath and between the large boulders. In one of
these little caves I found evidence of breeding with several old nests on
the floor and one still hanging. The last few times I visited (during the
1990's) I looked for but never saw the Rockwarblers. However, I haven't
been there for a few years so would be interested to know if anyone else
has seen them there recently. Evans Crown is separated from the nearest
sandstone country by several kilometres of cleared farmland, so it's
possible that what I saw was an isolated remnant population which died out.
As Mick mentioned, they are also found in limestone country within their
range - for example they can be readily found at Jenolan Caves.
Of course they are known to nest in man-made structures such as buildings
and mine-shafts, so sandstone caves are not a necessity for breeding.
However, from my own observations I suspect an essential factor is the
presence of a suitable projection, or lip, on the roof of the cave which
they can attach their nest to. I guess for this reason sandstone or
limestone caves are more often suitable than granite, which I think tends
to be smoother if and when it does actually form caves and overhangs.
It would be interesting to know if the Rockwarbler that Mick found in
granite at Kanangra Boyd is part of a breeding population there.
Cheers
Carol
At 12:21 PM +1100 1/2/04, Michael Todd wrote:
>While conducting bird surveys for NPWS this week in Kanangra Boyd NP (near
>Oberon, just to the west of the Blue Mountains, in NSW) I found a
>Rock-warbler in Granite country as opposed to the more usual sandstone
>country. This was a newey for me as I've only found them in sandstone
>previously. I understand that they can get into adjoining limestone country
>(Pizzey and Knight).
>
>I'm just curious about where others might have seen rock-warblers and
>whether my sighting was unusual or just run of the mill! Seeing as Carol
>can see rockwarblers in the middle of Katoomba it seems as though they can
>get into some unusual places!
>
>
>Cheers,
>
>Mick Todd
>Toronto, NSW
>
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